The Effect of Environmental Stresses on Gene Expression in Pathogenic spp. through Real-Time PCR.

Leptospirosis is a worldwide infectious and zoonotic disease. The incidence of this disease is high in temperate regions, especially in northern Iran. The aim of this study was to investigate the effects of temperature, pH, and plant extract on the gene expression in pathogenic spp. Fifty water samples were collected. Culture and PCR technique were used to isolate and identify the bacterium and the presence of the gene. The samples were exposed to different temperatures and pH levels for one day and the plant extract at different concentrations for one and seven days. RNA was extracted, and cDNA synthesis was performed for all the samples. All cDNAs were evaluated by the real-time PCR (SYBR green) technique. Out of the 50 samples, ten samples (20%), using PCR were determined to contain the pathogenic . Fold change of the expression of the gene associated with stresses was as follows: temperature stress of 40°C, 35°C, and 25°C reduced the gene expression in all three isolates, especially in the isolates type 1. The pH stress, i.e., pH values equal to 8 or 9 reduced the gene expression in three types of isolates, and pH = 6 stress increases the gene expression in the isolates of type 1. plant extract stress reduced the mentioned gene expression only in isolates of type 2. Temperature and pH stresses could lead to differences in the expression level and cause the gene expression decrease in three pathogenic isolates. The MIC results showed anti-leptospiral effect of plant extract.